Patterns of Cattle Farm Visitation by White-Tailed Deer in Relation to Risk of Disease Transmission in a Previously Infected Area with Bovine Tuberculosis in Minnesota, USA

Abstract

The main objective of this study was to characterize spatial patterns of white-tailed deer (Odocoileus virginianus) movement related to bovine tuberculosis (bTB) transmission risk to cattle in north-western Minnesota. Twenty-one adult deer (16 females and 5 males) were captured during winter (January-March) 2011 in areas adjacent to where an outbreak (2005-2009) of bTB occurred in deer and cattle. Deer were fitted with GPS collars programmed to collect deer location information every 90 min over a 15-month period. The exact locations of cattle, cattle feeding areas, and stored forage that were available to collared deer were assessed seasonally. In total, 47% (n = 9) of collared deer survived to the end of the study. Causes of mortality included wolves (n = 6), hunters (n = 1) and unknown (n = 2); additionally, 2 deer were censored due to collar malfunctions. Our results indicated that 5 deer (25%) had home ranges that included 6 cattle farms (20%). Most (77%) of the deer visits occurred in areas where cattle were present, with most visits (60%) from 00:00 to 06:00. March to May revealed the most farm visitations by deer (37%). This study provided baseline information regarding cattle-deer interactions critical to transmission of bTB in this region and suggested that risk mitigation practices should be implemented to separate wildlife and domestic livestock when feasible.

Persistent Spillback of Bovine Tuberculosis From White-Tailed Deer to Cattle in Michigan, USA: Status, Strategies, and Needs

“…Motivation also varies with circumstances relative to season (e.g., severity or length of winter, drought conditions in the summer) and availability of natural foods and water. Producers must be cognizant of these factors, and therefore, when risk is increased, must increase vigilance to maintain an effective level of biosecurity ( 26 , 36 , 37 ). Such mitigation measures and environmental influences are discussed during risk assessments to insure producers understand that wildlife risks are not static and identify factors and scenarios that may increase risk.…”

“…Annual whole-herd testing of cattle for bTB and outfitting cattle with radio-frequency identification (RFID) tags became a requirement for Michigan producers in the endemic area to move live cattle off their farms in 2007. These requirements enable trace-back investigations to locate where and when bTB-infected cattle shared the same space as other cattle, with the goal of identifying other potentially infected animals and premises ( 29 , 37 , 47 ). Although the infection of a herd due to movement of an infected cow into that herd occurs ( 48 ), it was presumed to be a lesser risk for cattle producers in Michigan than infected deer ( 29 , 47 ).…”

“…The frequency of visitation to highly-desirable resources such as stored feed and agricultural crops may be a learned behavior that could be curtailed by removing mature does or entire family groups of offending deer ( 64 ). It has been documented that fawns can learn movement patterns from adult does and that it is typically a few specific deer in a given area that will share space and time with cattle or frequent stored feed areas ( 27 , 36 , 37 ). As such, targeted removal of offending individuals may curb present and future visitation of farms by deer.…”

Bovine Tuberculosis Management in Northwest Minnesota and Implications of the Risk Information Seeking and Processing (RISP) Model for Wildlife Disease Management

“…Epidemiological evidence indicated the disease was introduced into a single beef cattle operation and from there it spilled over to deer ( 8 , 9 ). Deer presumably served as a spillover host for the transmission of the disease among area livestock operations ( 8 , 10 , 11 ).…”

Evaluating wildlife-cattle contact rates to improve the understanding of dynamics of bovine tuberculosis transmission in Michigan, USA

“…Transmission of M. bovis from animal to animal is possible through direct physical contact or exchange of air-borne pathogens, although transmission via contaminated feed or water is the most likely mode of transmission to cattle in the USA (Palmer et al, 2004a,b;Palmer and Whipple, 2006;Knust, 2008;Ribeiro-Lima et al, 2016). Human-manipulated environments, such as livestock production facilities, influence wildlife behavior and often provide unnatural foci for interaction such as at cattle-related resources including feed and water (Wobeser, 2006;Atwood et al, 2009;Gortazar et al, 2011;Barasona et al, 2014;Nunn et al, 2014).…”